Commitments and Contingent Liabilities (Details) (USD $)	Sep. 30, 2014
Parent Company [Member] \| Visa Membership [Member]
Loss Contingencies [Line Items]
Number of Visa Class B Shares Owned by Entity (in shares)	251,837
Number of Visa Class A Shares Visa Class B Shares Are Convertible To	103,782
BOKF Equity, LLC [Member]
Loss Contingencies [Line Items]
Number of Private Equity Funds of which the Entity is a General Partner	2
Contingent Obligations For Additional Investments in Private Equity Funds	$ 5,500,000
Cavanal Hill Funds [Member]
Loss Contingencies [Line Items]
Mutual Fund Investment in US Treasury Securities	1,100,000,000
Mutual Fund Investment in Cash Management	1,200,000,000
Mutual Fund Investment in Tax-Free Money Market Funds	$ 245,000,000
The Net Asset Value of Units in Mutual Funds (per unit)	1.00

Number of common stock class B owned by the entity

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Contingent obligation to make additional investments if limited partners are unable to perform.

No definition available.

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Carrying amount of mutual fund assets in cash management

No definition available.

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Mutual Fund Assets Managed investment in US Treasury Securities

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Amount of Mutual Fund Managed Assets in Tax-Free Money Market Funds

No definition available.

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Managed Net Asset Value of Units in Mutual Funds

No definition available.

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The number of consolidated private equity mutual funds that The Entity is a general partner of.

No definition available.

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Represents the number of Visa Class A shares that Visa Class B shares held by the Company are convertible to.

No definition available.

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